Automated brewing machines and other on-demand beverage systems for brewing beverages, such as coffee and tea, or for preparing food products usually have a reservoir, in which the brewing liquid, most commonly water, is heated by a heating element. The heated liquid is then pumped from the reservoir to a brewing chamber which holds brewing ingredients, such as coffee grounds or tea leaves. The heated liquid flows through the brewing ingredients to produce a brewed beverage. The beverage is then directed out of the brewing chamber into a container such as a jug or cup located beneath the brewing chamber outlet.
Many modern domestic beverage machines are designed to dispense individual servings of a beverage directly into a drinking receptacle, and derive the beverage from a bulk supply of beverage ingredients or from individual packages of beverage ingredients such as pods, pads or cartridges. Machines which use such individual packages reduce the need for cleaning and can enable the user to make a selection of beverages such as coffee, tea, hot chocolate and the like.
An example of one type of such cartridge is described in EP-A-1440903. The beverages are formed from brewing, mixing, dissolving or suspending the beverage ingredients in water or another liquid. For example for coffee beverages, heated water is forced through the cartridges under pressure to extract the aromatic constituents from the compacted coffee grounds contained therein. The use of cartridges in such machines has become increasingly popular due to their convenience and the quality of the beverage produced.
However, in order to try and minimise the packaging used in such single serve on demand machines, it has been proposed to replace the cartridges with tablets of compressed beverage or food product. Such tablets can conveniently be sold in a multipack format.
One of the problems that has been found with using compressed powder tablets in an on-demand machine is that of achieving a sufficiently rapid and even rate of dissolution, so that all of the powder is entirely dissolved. Conventional methods of dissolving tablets include breaking up the tablet by incorporating disintegrants or by crushing the tablet to increase the surface area. Once a tablet is crushed, it is possible that parts of the tablet are bypassed by a metered dose of water flowing through the brew chamber, with the result that the tablet may not be fully dissolved and the resulting beverage or food product is too weak.
It is well known that creating turbulence helps speed up the rate of dissolution of tablets. This can be achieved by methods such as mechanical agitation (stirring), ultra-sonic energy or by using high velocity water jets. The problem with a single water jet is that its energy dissolves the part of the tablet upon which it impinges, and so the jet must be moved over the tablet surface to promote even dissolution. Multiple jets acting on the tablet are a way of achieving better coverage, but the average flow rate and pressure must be increased proportionately to achieve the same jet velocity. If some jets break through the tablet before others then they simply waste energy and dilute the resulting beverage outflow.
It is an object of the present disclosure to provide an improved machine for the preparation of beverages and food products which utilizes a high energy water jet to break up a tablet of compressed ingredients, which overcomes these disadvantages.